Annoyingly, `longtable' steals `\kill' for its own purposes. Put it
back when we want it.
%%%--------------------------------------------------------------------------
%%% Environment for setting programs.
%%%--------------------------------------------------------------------------
%%% Environment for setting programs.
+%% Save `\kill' so that `longtable' won't clobber it.
+\let\prog@@kill\kill
+
%% Main guts of `prog' and `nprog'.
\def\@prog{%
\let\prog@@cr\@tabcr%
\let\@tabcr\@progcr%
%% Main guts of `prog' and `nprog'.
\def\@prog{%
\let\prog@@cr\@tabcr%
\let\@tabcr\@progcr%